Achieving high image quality in a printing assembly requires overcoming variants in static co-efficients and dynamic co-efficients of friction within a system. Controlling friction results in a precisely controlled speed, which is an important element of fine pixel placement. Also, pixel placement is a component of the media velocity as a marking element is placed on the sheet. Thus, it is desirable to control both the static and dynamic co-efficients of friction that are often associated with stick-slip, common to roller bearing systems.
Additionally, contemporary systems that exclusively use roller bearing elements for media carts are subject to wear and tear which further propagates miscalculations of velocity and/or position between the marking systems and the sheet to be marked. In this way, contemporary bearing surfaces and roller bearing assemblies make the repeatability of machine performance less consistent. Additionally, the wear and tear can increase the print head gap between print head surfaces and the substrate media sheet. When using inkjet technology, the downward spray of ink can fan out further than intended as a consequence of an increased print head gap, thus decreasing precision in the marking engine.
Additionally, contemporary roller bearing cart assemblies exhibit irregularities of positioning in a cross-process direction as well. Cart motion through a print zone is often accompanied by a cyclical back and forth motion across the marking zone resulting in nonlinear trajectory for the media cart and the sheet carrier thereon. Such a nonlinear trajectory can further diminish accuracy when attempting to mark the substrate media sheet.
Accordingly, it would be desirable to provide a media transport system and method for efficiently moving media through a print zone to permit high quality outputs and that overcomes other shortcomings of the prior art.